The present invention relates to composite members, and in particular to corrugated fiberglass panels having improved strength and stiffness.
Fiberglass panels are commonly constructed by using short chopped, randomly oriented fiberglass fibers or filaments and a resin. The fibers consist of chopped strands less than about 2 inches in length which are randomly arranged in the panel. The panel is molded into the shape of a corrugated member in a continuous process. Normally, the total weight of the filaments in such a panel is about 12-30 percent of the total weight of the panel. Such fiberglass designs are not intended to bear heavy loads since the transfer of loads through the chopped strands in the panel is haphazzard.
Another fiberglass construction technique uses a layer of continuous longitudinal unidirectional filaments and a layer of woven fiberglass filaments, known as woven roving, to lend strength to the article. See, for example, U.S. Pat. No. 4,029,172. This method produces stronger than conventional fiberglass panels but has some disadvantages.